<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>三列布局解决方案2-float+overflow</title>
  <style>
    * {
      margin: 0;
      padding: 0;
    }
    /* overflow: hidden;  BFC - IFC  
    不会和浮动容器进行重叠
    */
    #left{width: 200px;height:400px;background-color: saddlebrown;}
    #center{width: 200px;height:400px;background-color: green;}
    #right{height:600px;background-color: blue;overflow: hidden;}

    #left,#center{float:left;}
  </style>
</head>

<body>
  <div id="parent">
    <div id="left"></div>
    <div id="center"></div>
    <div id="right"></div>
  </div>
</body>

</html>